Re: [PATCH v3] hid/hid-multitouch: Keep latency normal on deactivate for reactivation gesture

[Werner Sembach]

Am 19.12.25 um 14:10 schrieb Benjamin Tissoires:
> On Nov 12 2025, Werner Sembach wrote:
> > Am 12.11.25 um 15:47 schrieb Werner Sembach:
> > > Uniwill devices have a built in gesture in the touchpad to de- and
> > > reactivate it by double taping the upper left corner. This gesture stops
> > > working when latency is set to high, so this patch keeps the latency on
> > > normal.
> > >
> > > Signed-off-by: Werner Sembach <wse@xxxxxxxxxxxxxxxxxxx>
> > > Cc: stable@xxxxxxxxxxxxxxx
> > > ---
> > > V1->V2: Use a quirk to narrow down the devices this is applied to.
> > > V2->V3: Fix this patch breaking touchpads on some devices.
> > >           Add another device ID.
> > >
> > > I have three Uniwill devices at hand right now that have at least two
> > > physically different touchpads, but same Vendor + Product ID combination.
> > > Maybe the vendor uses this product ID for all i2c connected touchpads, or
> > > it is used as some kind of subvendor ID to indicate Uniwill?
> > >
> > > To be able to really narrow it down to Uniwill only devices I would need to
> > > check DMI strings, but then I will probably narrow it down to much as I
> > > only know what we at TUXEDO use there.
> > >
> > >    drivers/hid/hid-multitouch.c | 26 +++++++++++++++++++++++++-
> > >    1 file changed, 25 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
> > > index 179dc316b4b51..ed9eb4e0d5038 100644
> > > --- a/drivers/hid/hid-multitouch.c
> > > +++ b/drivers/hid/hid-multitouch.c
> > > @@ -76,6 +76,7 @@ MODULE_LICENSE("GPL");
> > >    #define MT_QUIRK_DISABLE_WAKEUP		BIT(21)
> > >    #define MT_QUIRK_ORIENTATION_INVERT	BIT(22)
> > >    #define MT_QUIRK_APPLE_TOUCHBAR		BIT(23)
> > > +#define MT_QUIRK_KEEP_LATENCY_ON_CLOSE	BIT(24)
> > >    #define MT_INPUTMODE_TOUCHSCREEN	0x02
> > >    #define MT_INPUTMODE_TOUCHPAD		0x03
> > > @@ -211,6 +212,7 @@ static void mt_post_parse(struct mt_device *td, struct mt_application *app);
> > >    #define MT_CLS_WIN_8_DISABLE_WAKEUP		0x0016
> > >    #define MT_CLS_WIN_8_NO_STICKY_FINGERS		0x0017
> > >    #define MT_CLS_WIN_8_FORCE_MULTI_INPUT_NSMU	0x0018
> > > +#define MT_CLS_WIN_8_KEEP_LATENCY_ON_CLOSE	0x0019
> > A college realized that at some points in the code some, but not all, of the
> > MT_CLS_WIN_8* classes are checked for directly. Should I add my new class
> > there too?
> It depends. If it's truely a WIN_8 touchpad then I guess those checks
> are here for a reason, but if this particular device works without them,
> then it's your call in the end.

Didn't notice a difference, but will it include anyway to be on the safe side.

v4 incoming

> Cheers,
> Benjamin